Fire Safety Calculators | Professional NFPA Tools

Select a calculator above to begin your design or verification work.

Clean Agent / Gas Suppression System Calculator

Calculates required agent quantity (e.g., FM-200, NOVEC 1230) based on room size, temperature, and design concentration (NFPA 2001).

Room Dimensions

Room Length (ft):

Room Width (m):

Room Height (m):

Room Temperature (°F):

Design Parameters

Selected Agent (Affects formula constants):

Design Concentration (%): 7.5% is common for Class A/C hazards using FM-200.

Altitude (ft): Higher altitude requires more agent.

Water Mist System Calculator

Estimates basic water demand for initial system sizing based on hazard area and density requirements.

Protected Area (Sq Ft):

Required Density (GPM/Sq Ft): Varies greatly by system listing (e.g., 0.05 GPM/SqFt is illustrative).

Discharge Duration (Minutes):

Foam System Calculator (NFPA 11)

Calculates the required foam concentrate volume for a spill fire based on application standards.

Spill / Tank Surface Area (Sq Ft):

Foam Concentrate Type:

Application Rate (GPM/Sq Ft): 0.10 GPM/SqFt is typical for hydrocarbon spill (NFPA 11).

Discharge Duration (Minutes):

CO₂ System Calculator

Calculates the minimum CO₂ required for total flooding based on room volume and hazard.

Room Length (ft):

Room Width (m):

Room Height (m):

Hazard Type (to determine required concentration):

Smoke Detector Spacing Calculator (NFPA 72)

Calculates maximum allowable spacing for spot-type smoke detectors based on ceiling characteristics (NFPA 72, Table 17.5.3.2.1).

Ceiling Height (ft):

Ceiling Type:

Battery Standby Calculator (NFPA 72)

Determines the minimum required Amp-hour (Ah) rating for fire alarm backup batteries.

Total Standby Current (Amps): Total current draw of the panel and devices in non-alarm state.

Total Alarm Current (Amps): Peak current draw when all notification appliances are active.

Required Standby Time (Hours): Minimum 24 hours per NFPA 72.

Required Alarm Time (Minutes): Minimum 5 minutes for non-voice systems, 15 minutes for voice evacuation.

Voltage Drop Calculator

Calculates voltage loss on a wire run to ensure notification appliances receive sufficient power.

Wire Gauge (AWG):

One-Way Wire Length (ft): Length from panel to end-of-line device.

Total Circuit Current Draw (Amps): Total draw of all devices on the circuit.

Source Voltage (Volts DC):

Notification Appliance Circuit (NAC) Load Calculator

Calculates the total current load on a fire alarm circuit to prevent panel overload.

NAC Circuit Limit (Amps): Max current capacity of the NAC terminal on your panel.

Number of Strobes/Horns:

Strobe/Horn Current Draw (Amps per device): Read from the device specification sheet (e.g., 0.08 A).

Number of Speakers (if separate):

Speaker Current Draw (Amps per device):

Fire Stopping Material Calculator

Estimates the volume of fire sealant/mortar required for annular space around a penetration.

Opening Diameter (Inches):

Penetration Diameter (Inches):

Required Depth/Thickness (Inches):

Fire Door Inspection Checklist Generator (NFPA 80)

Interactive checklist to verify essential fire door components are compliant. (Non-Calculator Tool)

Door Integrity Check

1. Door Gaps: Are the clearances (top, sides, bottom) less than 3/4 inch?

2. Latching: Does the door latch securely when closed?

3. Self-Closing: Does the door close and latch without manual assistance?

4. Hardware: Are all hinges/parts secured and in good condition (no missing screws)?

Fire & Smoke Damper Selection Guide

Interactive wizard to recommend the correct damper type based on location and rating requirements. (Non-Calculator Tool)

Selection Criteria

1. Location of Damper:

2. HVAC System Status in a Fire:

Occupant Load Calculator (NFPA 101 / IBC)

Calculates the maximum number of people allowed in a space based on floor area and use.

Net or Gross Floor Area (Sq Ft):

Occupancy Type & Load Factor: Factors are based on NFPA 101/IBC. Area/Factor = Occupant Load.

Egress Width Calculator (NFPA 101 / IBC)

Calculates the minimum total required width for exit doors and corridors.

Calculated Occupant Load:

Means of Egress Component:

System Protection Level:

Emergency Lighting Point Calculator

Estimates the distance between emergency light fixtures to meet minimum coverage requirements.

Mounting Height (ft):

Light Output / Lux Factor (Lumens/Candlepower Rating): Use the fixture's listed photometric data (e.g., 500 Candelas).

Minimum Required Illuminance (Foot-Candles or Lux): 1.0 ft-c is required for path of egress (NFPA 101/IBC).

Hydrant Flow Calculator (Pitot)

Calculates available water flow (GPM) from a fire hydrant using a Pitot gauge reading.

Pitot Pressure (PSI):

Hydrant Outlet Diameter (Inches): Typically 2.5" or 4.5".

Discharge Coefficient (C): Use 0.90 for smooth, open butt; 0.70 for rough/obstructed.

Friction Loss Calculator (Hazen-Williams)

Calculates pressure loss due to friction in pipework.

Pipe Inside Diameter (Inches):

Flow Rate (GPM):

Pipe Length (m):

Pipe Material (Hazen-Williams C-Factor):

Required Fire Flow (RFF) Calculator (NFPA 1142)

Estimates the required fire flow for a commercial/industrial building based on construction and area.

Total Floor Area (Sq Ft):

Construction Type Coefficient (C): F = 18 * C * sqrt(A) in GPM, with safety factors.

Fire Pump Sizing & Head Calculator

Calculates the required pump head (pressure) based on demand and system losses.

Required System Flow (GPM):

Pressure at Demand Point (PSI): Minimum required pressure at the furthest sprinkler/hose connection.

Total Friction & Minor Loss (PSI):

Elevation Head Loss (PSI): Pressure needed to overcome height difference between the pump and the demand point.

Minimum Available Suction Pressure (Bar): Pressure supplied to the pump from the city water main or tank.

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